Case Studies

  • The role of diagnostic testing in establishing bovine vaccination programs

    Vaccination programs are integral to the overall health and profitability of a cattle operation. Without vaccinations, diseases such as Bovine Respiratory Disease (BRD) and Bovine Viral Diarrhea (BVD) can decimate a cattle herd. The Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) team includes experienced veterinary diagnosticians available to help veterinarians and producers with a vaccination…

  • Johne’s disease: how are cattle affected?

    The Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) has seen quite a few cattle testing positive for Johne’s Disease. Clinically affected cattle are usually mature adults that are gradually losing body condition despite having a normal appetite. Chronic watery diarrhea is also usually recognized, but it can be sporadic during the syndrome. The causative organism…

  • Unusual manifestation of papular stomatitis in a feedlot steer

    A male-castrated, crossbred steer was noted to have a severe and locally extensive skin disease involving the perineal and inguinal areas with other scattered individual nodular skin masses on other portions of the body (Figure 1). The animal was otherwise healthy and displayed no discomfort from the skin lesions. Fresh and fixed skin lesions were…

  • Nitrate poisoning in cattle

    Recently, seventeen cows died within twenty-four hours after consuming new hay. All of the cows died within 100 yards of the hay. A sample of the hay, along with tissue samples and ocular fluid from one of the cows were submitted to the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) for testing. Toxic levels of…

  • Zinc contamination in serum samples

    The Texas A&M Veterinary Medical Diagnostic Laboratory’s (TVMDL) analytical chemistry section performed zinc testing on a small set of paired samples. Prior to testing, blood was collected from four clinically healthy animals and divided into two tubes with EDTA. One tube was a standard microtainer tube with a rubber o-ring buried in the groove of…

  • Gangrenous dermatitis diagnosed in bobwhite quail

    Seven dead, 16-week-old bobwhite quail were presented to the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) in Gonzales for necropsy. The history provided noted increased mortality of about 15 birds per day, with no clinical symptoms.  The birds were in flight pens with no vegetation.  Additionally, all birds had varying degrees of feather loss around…

  • Duodenitis/proximal jejunitis (DPJ) in a horse

    A 5-year-old Andalusian stallion was presented for necropsy at the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) after being euthanatized due to a history of colic, profuse nasogastric reflux, non-response to treatment, and poor prognosis. Upon opening the abdomen at necropsy, the stomach was found to be severely distended with gas. The duodenum and proximal…

  • Contagious ecthyma diagnosed in a young goat

    The body of a 3-month-old goat was submitted to the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) in College Station. This goat had been purchased 3 weeks prior. The goat was euthanized due to sudden onset of neurological signs and was also noted to have a crusty lesion on the lip. Gross necropsy confirmed there…

  • Coffee senna poisoning in cattle

    Approximately 200 head of cattle were grazing on improved native Bermuda grass pastures in the Colorado River bottom. Vegetation also included a large number of oak trees, and a low number of nightshade, cocklebur, and coffee senna plants. Two 400 to 500 lb. calves were found down and unable to rise. Both calves died within…

  • Demodex mites discovered in a white-tailed deer

    A haired skin specimen from a white-tailed deer of unknown age was submitted to the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) for microscopic examination. The tissue was from a deer that had multiple cutaneous, firm, tan nodules. Microscopically, these tan nodules correlated with markedly dilated hair follicles that contained a large number of cross…